Ammonia-gas detector



NOV. 4, 1939. HAVENS, JR 1,780,483

AMMONIA GAS DETECTOR Filed Oct. 5. 1928 3 Sheets-Sheet l W 1936 L. A. HAVENS. JR 1330,4813

AMMONIA GAS DETECTOR Filed Oct. 5, 1928 3 Sheets-Sheet 2 Lamas ff j fdg/Gfld, D5.

j fi' 23 Inventor Nov. 4, 1930. .1 A. HAVENS. JR ,7 ,483

AMMONIA GAS DETECTOR Filed Oct. 3, 1928 3 Sheets-Sheet 3 I .IZ'LI' EEL l nails 11 .Ha vens, rfr'.

Patented Nov. 4, 1930 LOUIS A. HAVENS, JR.,- F QUEENS VILLAGE, NEW YORK AMMONIA-GAS DETECTOR Application filed October 3, 1928. Serial No. 309,975.

The present invention relates to improvements in circuit makers and closers and has reference. more particularly to a device for association with ar'efrigerating plant where- I in ammonia is employed as the refrigerant.

One of the important objects of the present invention is to provide a means for closing an electric circuit to actuate an alarm or cut off the flow of the gas when a leak occurs in the pipe line thus providing a safety device for association with an ammonia operated refrigerating plant.

A further object is to provide an ammonia gas detector that will at all times be positive and efficient as well as automatic in its operation, the device being further simple in construction, inexpensive, strong and durable and further well adapted to the purposes; for

which it is designed.

Other objects and advantages will become apparent during the course of the following description. i i

In the accompanying drawing, forming a part of this specification and in which like numerals indicate like parts throughout the same:

Figure 1 is a sectional view through the ammonla gas collecting hood showing the circuit maker and breaker constituting the present invention arranged therein,

the cover therefor being removed,

Figure 6 is a detail perspective view of the liquid container or receptacle per se,

Figure 7 is a detail showing the manner in which the fine wire mesh screen is associated with the frame of the liquid container, and

Figure Sis a sectional View taken approximately on the line 88 of Figure 1 illustrat- -ing one'of the contacts.

In-the drawings wherein forthe purpose f illustrationisshown the preferred embodiment of my invention, the numeral 1 designates a hood in which the ammonia or other gas used in conjunction with a refrigerating apparatus that accidentally escapes when a leak occurs in the gas line is collected for actuating the circuit maker and breaker embodying the present invention.

The top of the hood is provided with a suitable opening 2 through which projects the upper portion of a substantially rectangular shaped open top reservoir 3 that is adapted to contain a reserve supply of water or other aqueous solution.

A removable cover 4 is provided for the open top reservoir. The present invention in eludes the provision of a base 5 located within the hood and extending upwardly from the rear end of the base is the standard 6 that supports at its upper end portion the reser- A pair of forwardly extending through the forward ends of the spaced brackets in the manner as clearly suggested in Figure 4.

A substantially rectangular shaped frame 10 is formed in its sides adjacent the rear end thereof with registering openings 11 to accommodate the transverse rod 9 whereby said frame is pivotally supported adjacent its rear end between the forwardly extending brackets in the manner as also clearly illustrated in Figure 4.

A cross bar 12 extends between the sides of the frame at a point forwardly of the registering openings 11 and secured over the sides of the forward end portion of the frame 10 and over the forward end and the cross bar 12 is a fine wire mesh screen 18, the central portion of which is dished whereby to provide what I term as a receptacle for the liquid or aqueous solution.

The foraminous material is of such a nature as to prevent the water or aqueous solution passing therethrough as long as there is nothing to come in contact with the water that would alter its surface tension.

This receptacle or container is denotedfree end of this latchengages with a pin 18" that projects laterally from the vadjacent bracket 7 as shown very clearly in Figure I.

A vertically disposed tube 19is varranged within the reservoir 3 adjacent the front side thereof and the lower end of this tube extends Y downwardly through the bottom of the reservoir for disposition directly above the rear portion of the liquid container or receptacle14 as shown in Figures 1 and 3.

. It will be observed upon referring toFigure 3 that the upper end of the tube 19 terminates at a. point below the upper edge of the reservoirand'at a point above the water level in saidreservo'ir. V A

A wick 20 of relatively long length is submerged within the liquid within the reservoir or the major portion thereof, the outer end of the wick extending downwardly through the tube 19. The purpose of thiswick is to apply the liquid to the container 14 to replace that which is lost by reason of evaporation.

The circuit maker and breaker associated with the present invention comprises a block 21 that issecured on the outer face of an upwardly disposed extension 22 formed on the bracket 70f the forward end thereof and as is clearly shown in Figure 8, the block 21 is insulated with respect to the extension 22.

A pair of spaced contacts 23 and 24 are arranged within suitable sockets provided in the top portion of the block 21 and as is clearly illustrated in Figure 8, each of the sockets provided for the aforesaid contacts is lined with insulation denoted by the reference character 25.

A terminal 26 extends through the bottom of each socket 27 and an expansible coil spring 28 is arranged in each socket for disposition between the heads of the terminal and the lower end of the respective contacts for normally urging the spring contacts upwardly in their respective sockets so that the upper ends of these contacts normally project beyond theupper surface of the block 21. The terminals 26 are also insulated with respect to the block 21 and the lower ends of these terminals provide binding posts to which are attached the wires 29 that are connected to an appropriate alarm or signal to a source of electrical supply, not shown.

The circuit to such signal is normally open and for the purpose of closing this circuit to effect the actuation of the signal or alarm,-

there is provided in conjunction with the.

present invention, a contact bridging plate 30 that projects laterally from the side of the frame 10 and this plate is insulated from the frame as suggested in Figure 6.

The plate is' disposed directly above the contacts 23 and 24 as suggested very clearly in Figure 1 and the manner in which this bridging plate cooperates with the afore mentioned spaced contacts will be presently described. j V. While I have mentioned the use of the device as being adapted to operate an alarm or signal, it may be equally as well adapted for use inactuatingthe' valve mechanism in the pipe lines that supply theaminonia or other refrigei-ati g gas tothe' refrigerating apparatus byemploying any well known valve actuating mechanism that is controlled bythe' closing of an electric circuit.

The operation of my'iinproved ammonia gas detector may be briefly stated follows.

Water or other aqueous solution is placed in the container 14 and as long as nothing comes in contact with the water that would cause the. alteration of surface tension or density, the water cannot leak through the foraminous screen 13. Thus the' weighted receptacle. is held'in' the horizontal position keeping the plate 30 maintained out of en gagement with the spaced contacts 23 and 24 thus keeping the circuit to thesignal or valve actuatingmechanisin open; 7

However when the ammonia .or other gas that is collcted in the hood- 1, from leakage in the refrigerating. system, comes in contact with the liquid in' the receptacle or con tainer 14, and said liquid absorbs the gas to the extentthat the surface tension of the liquid in the receptacle is lowered, the liqwill allow the weight 16 to" swing the pivoted frame. 10 downwardly in a rearward direction whereupon the plate30will bridge 7 the contacts 23' and 24 thus closing the circuit to the signal 01' valve actuating mechanism. V 7 I The reservoir 3 provides a means for reei plenishing the liquid in the receptacle 14 that is lost by r ason of evaporation and the liquid is conducted from the reservoir to the receptacle through the medium of the with The drain or overflow opening. 15 will compensate for the fast feeding of the liq uid to the container, An aqueous solution of theflproper specific gravity is employed when the device is used where temperatures are low,to prevent liquid from freez It will thus be seen froiii the fdiegoing vi are:

descripticiii, that I have prev-idea r a leak occurs in the pipe that supplies the refrigerant to the apparatus and in this manner said device will enable repairs to be made immediately and at the same time preventing an undue waste of the ammonia.

The simplicity in which my device is constructed enables the parts to be readily and easily assembled or disassembled and furthermore the detector will at all times be positive and etlicient in carrying out the purposes for which it is designed.

l/Vhile I have shown the preferred embodiment of my invention, it is to be understood that various changes in the size, shape and arrangement of parts may be resorted to without departing from the spirit of the invention and the scope of the appended claims.

Having thus described my invention, what I claim as new is:

1. A gas detecting apparatus comprising in combination, a gas collecting hood, a standard arranged within the hood, a vertically swinging liquid container having a foraminous body, a circuit closer structure operatively associated with the pivoted container and the support and normally held in an inoperative position by the weight of the liquid in the container, said circuit closer structure being disposed in an operative position when the gas collected in the hood comes in con tact with the liquid in the container to lower the surface tension thereof and to cause the liquid to flow downwardly through the fora-minous body of the container.

2. A gas detecting apparatus comprising in combination, a gas collecting hood, a standard arranged within the hood, a vertically swinging liquid container having a foraminous body, a circuit closer structure cooperatively associated with the pivoted container and the support and normally held in an inoperative position by the weight of the liquid in the container said circuit closer structure being disposed in an operative position when the gas collected in the hood comes in contact with the liquid in the container to lower the surface tension thereof and to cause the liquid to flow downwardly through the foraminous body of the container, and means for effecting the swinging movement of the pivoted container to dispose the closer structure in an operative position when the container becomes emptied.

3. A gas detecting apparatus comprising in combination, a gas collecting hood, a standard arranged within the hood, a vertically swinging liquid container having a foraminous body, a circuit closer structure cooperatively associated with the pivoted container and the support and normally held in an inoperative position by the weight of the liquid in the container, said circuit closer structure being disposed in an operative position when the gas collected in the hood comes in contact with the liquid in the container to lower the surface tension thereof and to cause the liquid to flow downwardly through the foraminous body of the container, and means for effecting the swinging movement of the pivoted container to dispose the closer structure in an operative position when the container becomes em )tied, and a reservoir ar ranged on a support above the container for replenishing the liquid lost by evaporation.

l. A gravitationally movable control device for containing water, having a screen bottom adapted to prevent the passage of water through its interstices as long as the water is inatfected by anything that would alter the surface tension thereof and also adapted when the surface tension of the water is lessened to allow the water to pass through its said interstices.

5. A gas detecting apparatus comprising in combination, a support, a foraminous liquid container pivoted to the support, a circuit clos r structure mounted on the support and cooperatively associated with the liquid container, said circuit closer normally held in inoperative position by the weight of the liquid in the interstices of the container and in the operative position when the interstices are free of liquid, a liquid reservoir mounted on the support, a conduit connected with the reservoir for supplying liquid to the container, and said support adapted to be disposed in proximity to gas conductors and receptacles in a refrigerating system for the purpose of permitting gas leakage to contact with the liquid held in the interstices of the container to decrease the surface tension of the liquid and cause said liquid to free itself from the container.

6. A gas detecting apparatus comprising in combination, a support, a foraminous gravitationally movable liquid container connected with the support, a circuit closer structure mounted on the support and cooperatively associated with the liquid container, said circuit closer normally held in inoperative position by the weight of the liquid in the interstices of the container and in the operative position when the interstices are free of liquid, a liquid reservoir mounted on the support, a conduit connected with the reservoir for supplying liquid to the container, and said support adapted to be disposed in proximity to gas conductors and receptacles for the purpose of permitting gas leakage to contact with the liquid held in the interstices of the container to decrease the surface tension of the liquid and cause said liquid to free itself from the container.

7. In a circuit closer, a support, a pair of electrical conducting terminals connected with the support, a gravitationally movable switch arm connected with the support, said arm having a foraminous layer of material thereon to prevent liquid under normal con 4' memes di bi'ons from passing thei'ethi'ough and means" connected with the arm for bridging said terminals when the layeris freed of liquid by contacting with a gas that causes a diminished surface tension in the liquid.

In testimony whereof I aflix my signature.

LOUIS A. HAVENS, JR. 

